How much respect do you owe someone you’re being forced into a relationship with, who you don’t trust, but who hasn’t hurt you yet? (in this case, a therapist)
realsocialskills said:
First and foremost: I’m not sure that it’s actually true that they haven’t hurt you yet. They’re agreeing to be your therapist against your will. That’s already something they’re doing to you, in itself. Therapy is an emotionally intimate relationship, and intimacy requires consent. 
Beyond that, I think in this particular situation, it might be more helpful to talk about what you don’t owe them:
You don’t owe them deference or even cooperation. Your mind is yours, and your life is yours, and you don’t have to take their opinions into account unless you decide that you value them.
You don’t owe them respect for their professional opinion. That’s something they earn, and it’s a judgment that you get to make. Their degree does not entitle them to have you regard them as an expert in your life, mind, or mental condition.
You don’t owe them intimacy. You don’t owe them personal information about yourself. You don’t owe them answers to their questions.
You don’t owe them the truth. 
You don’t owe them any trust, at all. Trust is earned, and something you have to give freely. They are not entitled to your trust or intimacy just because someone made you sit in a room and talk to them. 
You don’t owe them politeness, although for the sake of your safety, I would advise you to be as polite as you can stomach. It’s safer.
You don’t have to wait for them to hurt further you before you decide not to trust them. Trusting them, or not, is your call. Trust has to be earned and freely given, and you can revoke it at any time. Even in therapy that you enter into voluntarily and really want, trust in a therapeutic relationship has to be built over time. It’s never automatic or instant. It’s ok not to go in trusting. You are not wronging them in any way by being reluctant to discuss deeply intimate things with a stranger you’re coerced into spending time with.
This is all still true even if it turns out that they are a good therapist, or if they’ve successfully helped other people. They may be an amazing therapist for people who are consenting. They may be genuinely trying to help you. They may have helped many other people. They might be able to help you if you let them. Even if all of that is true, you still have every right to decide for yourself whether or not you want a therapeutic relationship with them. (Much as even if you’re lonely and there are all kinds of reasons that a particular person might be an amazing partner, it’s still ok to decide not to date that person.)
tl;dr: I’m sorry that you’re in this situation. I’m sorry you’re facing whatever led to this, too. You don’t owe this therapist trust or intimacy. If you decide you want a therapeutic relationship with them, that’s your choice to make, but it’s not something you owe them. I hope you’re ok.